Details

In order to address various demanding requirements emanating from high temperature operation, following are some of the key features to be considered in pump design.:-
1. Heating of the pump from atmospheric condition to the operating high temperature of the liquids results in considerable linear expansion of the pump casing, shaft and other wetted parts. Centreline support of casing for temperature above 200o C. is an Industry norm, to negate the change in alignment between driver and pump.
2.Differential thermal expansions calls for careful selection of running clearance for wetted mating parts.
3. Consideration of steam Jacketing of pump casing to bring at a reasonable temperature accounting for heat losses, so as to enable hot start-up of pumps, where so desired.
4 Pump to motor alignment protocol to be reasonably established to account for changes in position of drive motor shaft centreline and pump shaft centreline, while it operates at high temperature.
5. Mechanical seals to be appropriately selected including suitable quenching facility, flushing liquid cooling, Jacketed stuffing box cooling, proper venting of stuffing box to avoid vapour blocking, and eventual dry running of seals and damage.
6. Installation of suitable cooling plans for bearing housing with fins cooling, heat shield/deflectors, and cooling fans in some cases as needed.
7. For high temperature liquids operating near boiling point at the operating pressure condition, NPSH margin consideration is inevitable to avoid cavitation.